| [ Summary ] |
Space flight in a reduced gravity environment can have lasting effects on the body. For example, astronauts undergo a significant drop in bone mineral density during space missions, but the molecular mechanisms responsible for such changes in bone density are unclear. To identify these mechanisms, two unique experiments were performed at the International Space Station, using medaka fish. The first was a long-term experiment that analyzed bone growth over a period of 2 months and showed decrease in the mineral density of pharyngeal teeth and bones. The second was a short-term experiment involving live imaging of transgenic medaka lines and transcriptome analysis over 8 days. The results indicated increased expression levels for 5 genes. Taken together, medaka fish studies give scientists a good starting point to assess how the process actually occurs. |